Mexican authorities say seven adult members of a family have been killed in a popular beach resort city in the southern state of Oaxaca.

The Oaxaca state prosecutor's office said Monday in a statement that the seven men were "shark fishermen" and an early line of inquiry is whether they may have been involved in other activities while at sea. The statement did not mention drug trafficking, but drugs are often transported along Mexico's coast.

Prosecutors say armed men arrived around 10 p.m. Monday outside the men's home in downtown Puerto Escondido and entered shooting those inside. Four men died inside the home and three others died while receiving medical treatment. One person was wounded and survived.

Oaxaca has largely avoided the drug violence plaguing other states.